Need help with mouse not working in UI

[Gyro]

So this problem is rather unique because a friend of mine want to use right click as shooting button, and left click as zooming scope instead of the normal human way. Of course when he unbinds the left click, he can't use it to access the UI, can't left click to choose anything. CS2 doesn't seem to allow key combinations neither, so when I told him to try something like binding ctrl+left click as shooting and right click as shooting so maybe he could use ctrl+left click to access the UI options, we couldn't find a way to do that even in config files. Help much appreciated.

[onemeow]

I think you don't need to bind anything in game, just go to your windows mouse settings, and check "Switch primary and secondary buttons" checkbox.